Liquid drug container

ABSTRACT

A liquid drug container comprises a container body  1 ; a nozzle member  2  liquid-tightly mounted on the container body  1 ; and a nozzle cap  6  fitted on the nozzle member  2 . A nozzle hole  231  of the nozzle member  2  is covered with a hydrophilic filer  3 , and a top wall of the nozzle member  2  is provided with an air hole  24  covered with a hydrophobic filter  4 . The nozzle member  2  may be provided with a filter-mounting member  8  for attachment of the filters. Also, the nozzle member  2  may be provided with a flow control member that controls air flowing into the container body through the air hole.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority under 35 U.S.C. §119 to JapanesePatent Application No. JP 2002-102911, filed Apr. 4, 2002; JP2002-212231, filed Jul. 22, 2002; and JP 2002-336579, filed on Nov. 20,2002, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a liquid drug container and, moreparticularly, a liquid drug container used for preservation of liquiddrugs or liquid cosmetics and so designed that the interior of thecontainer is prevented from being contaminated by bacterium ormicroorganisms.

2. Background Art

In containers used for preservation of liquid chemicals or liquidcosmetics, an interior of the container is not aseptically isolated fromthe exterior. Thus, if the container is unsealed to bring it into use,the interior of the container is exposed to the atmosphere through anozzle of the container. Thus, there is a fear that floating bacteria inthe atmosphere may invade the interior of the container through thenozzle. On the other hand, if the nozzle is brought into contact withthe skin during use, there is a fear that the interior of the containeris easily invaded by bacterium or microorganism adhered to the skin.Further, as the liquid drug container of this kind, there have been usedsuch containers that discharge a content thereof under pressure of ahand and restore to the original configuration after release of thepressure applied thereto. At the time of return to the originalconfiguration, the deformed container sucks in the surrounding air.Thus, there is a fear that bacteria and microorganism in the atmosphereare sucked in the interior of the container along with the air flowinginto the container.

Accordingly, the liquid drug containers of the prior art are at highrisk of multiplication of bacteria or microorganisms in the containerbody as the invaded bacteria or microorganisms take active constituentscontained in the drug, buffer solutions added for stabilizing the liquiddrug, or solubilizing agent as nutrients.

For purposes of antisepsis, sterilization or antibacterial activity, itis common practice to incorporate various kinds of preservatives intothe liquid drugs of the prior art to prevent multiplication of bacteriaor microorganism even if the container is invaded by bacteria ormicroorganism. The generally known preservatives include antiseptics ofquaternary ammonium salts exemplified by benzalkonium chloride andbenzethonium chloride. However, such salts are limited in use because oftheir strong stimulation and cytotoxic effects. Particularly, they cannot be used as antiseptics for liquid drugs applied to eye tissues ororgans sensitive to stimulus.

In recent years, reports have been made on so-called chemicalhypersensitivity, i.e., symptom of serious allergy to chemical compoundssuch as preservative. For that reason, some chemicals and cosmeticscontaining no preservative have been developed and put to practical use.However, if the chemicals or cosmetics do not contain any preservative,it is impossible to ensure aseptic conditions after unsealing. Thisnecessitates packaging of a dosage of such a chemical solution or aliquid cosmetic in a single disposable container, entailing an increasein production costs and space-consuming. Thus, the chemicals andcosmetics do not contain any preservative fail in popularization.

On the other hand, it has been proposed to make the container with aplastic deformable body (Examined Japanese utility model publication No.S63-184037, Japanese translation of PCT international application No.2001-521865) to prevent invasion of floating bacteria or microorganism,which results from inflow of the atmosphere which occurs at the time ofrestoring of the pressure-deformed container to its original state bythe pressure release after discharge of the liquid drug.

However, even if the container is of plastic deformable body, there isno change in the fact that the medical solution contained therein isexposed to the atmosphere through a dispensing nozzle. Thus, it isimpossible to completely prevent invasion of bacteria and microorganism.

Further, there have been proposed some containers of the kind whereinthe nozzle is provided with a filter to prevent invasion of bacteria andmicroorganism, which may take place when the liquid drug remained in thenozzle is returned to the container body after use, or when theelastically deformed container is restored to its original state by thepressure release (cf. Examined Japanese utility model publication No.S35-592, Examined Japanese utility model publication No. S35-31875).

However, even if the nozzle is provided with a filter, it is impossibleto trap unobservable bacteria or microorganism since the filter, whichallows both liquid and gas to pass therethrough, generally has a largebore size.

To this end, it has been proposed to provide the container with ahydrophilic filter or a hydrophobic filter that enable to trapunobservable bacteria or microorganism. However, if the filter is ahydrophilic filter, it is unable to allow the pressure-deformedcontainer to restore to its original configuration since the hydrophilicfilter prevents flow of the gas though it allows the liquid to passthrough.

In order to allow the container to restore to its originalconfiguration, it has been proposed a container provided with ahydrophobic filter allowing the atmosphere to flow in the container((cf. Examined Japanese Patent publication No. H03-61461).

Since the nozzle hole serves as an air hole, the hydrophobic filterlimits inflow of the atmosphere when the liquid drug that flows backfrom the nozzle is retained on the hydrophobic filter. Thus, thepressure-deformed container can not be restored to the originalconfiguration.

Further, there is a container so designed as to block inflow of theatmosphere into the container to prevent invasion of bacteria (cf.Published Japanese Patent application No. JP2002-80055A).

As shown in FIG. 14, a container 102 of an embodiment of the above priorart includes a plug body 103 fitted in a mouth thereof. The plug body103 is a top-closed cylindrical member, into which a top-closed fittingmember 134 is fitted to form a space between a top of the plug body 103and a top of the fitting member 134. The plug body 103 is provided witha nozzle 131 at a central part of the top thereof, while the fittingmember 134 is provided with a valve hole 106 at a central portion of thetop thereof. A filter 107 is arranged on a bottom side of the nozzle131, and a check valve 108 is arranged on a upper side of valve hole106. A space formed between the filter 107 and the check valve 108serves as a space 109 holding a liquid drug.

In use, by exerting pressure on the container 102 with hand after takingoff an outer cap 140, the liquid drug in the container passes throughthe valve hole 106, pushes the check valve 108 open, fills the holdingspace 109, and spouts from the nozzle 131. By loosing the pressure onthe container 102, the container 102 begins to restore to the originalconfiguration and produces a negative pressure, so that the discharge ofthe liquid drug is stopped. At the same time, the check valve 108 isclosed and thus the container 102 is prevented from inflow of theambient air even if the air flows in through the nozzle 131.

However, there is a fear that the liquid drug stays in nozzle 131, whichin turn causes a fear of bleeding of bacteria in the tip portion ofnozzle 131 being in direct contact with the ambient air. The thuspolluted liquid drug is used for a patient in the next use. Even in theembodiment of the prior art, it is impossible to keep aseptic conditionsof the liquid drug.

SUMMARY AND OBJECTS OF THE INVENTION

The present invention has been made in view of the aforesaidcircumstances and aims at providing a liquid drug container of the kindwherein the container is adapted to discharge a liquid drug containedtherein through a nozzle hole by applying a pressure, and then return tothe original configuration thereof by releasing the applied pressure,and wherein the container is prevented from invasion of bacteria ormicroorganism even if the nozzle had been brought into contact with askin with much saprophyte, such as fingers or a side.

According to the present invention, the above object is achieved byproviding a hydrophilic filter that covers a nozzle hole of a liquiddrug container; providing an air hole separate from the nozzle hole,said air hole being adapted to communicate an interior of the containerbody with an exterior of the container body, in stead of the nozzle holethat has lost the air permeability at the time of wetting of thehydrophilic filter; and covering said air hole with a hydrophobicfilter.

A liquid drug container according to the present invention comprises acontainer body having a mouth at one end and being deformable under thepressure, a nozzle member liquid-tightly mounted on the mouth of thecontainer body, and a nozzle cap mounted on the nozzle member, whereinsaid nozzle member is provided with a nozzle hole for discharging aliquid drug contained in the container body, and an air hole forcommunicating an interior of the container body to the exterior thereof,and wherein said nozzle member is further provided with a hydrophilicfiler for covering said nozzle hole, and a hydrophobic filter forcovering said air hole.

The container body is made of a flexible material which is elasticallydeformable under the pressure and easily restorable to the originalconfiguration by release of the applied pressure, for example, one ofvarious elastic polymers such as polypropylene, polyethylene,polyethylene terephthalate, polyethylene telenaphthalate, polyester,plasticized polyvinyl chloride, thermoplastic elastomer andpolycarbonate.

The nozzle member comprises a top wall covering the mouth of thecontainer body, a skirt portion extending from a periphery of the topwall toward a proximal end of the nozzle member, and a nozzle providedat a central area of the top wall and extending toward a distal end ofthe nozzle member. The nozzle hole passes through the top wall andextends to the tip of the nozzle. In addition to the nozzle hole, thetop wall is provided with an air hole passing therethrough at a positionspaced from the nozzle hole.

It is preferred that the hydrophilic filter and hydrophobic filter arein the form of a membrane and are welded to the inner side of the topwall of the nozzle member so as to cover the nozzle hole or air hole,respectively. Such filters are classified broadly into two categories,i.e., a “depth type” that traps bacteria within the filter, and a“screen type” that traps bacteria on surfaces of the filter, both ofwhich can be used for the container of the present invention. It ispreferred that the hydrophilic filter and hydrophobic filter have a boresize of 0.45 μm or below, more preferably, 0.22 μm or below to preventCandida albicans, Pseudomonas genera and Burkholderiacepacia, which aregenerally known as pollutive bacteria, from invading the interior of thecontainer.

In order to improve the flow of liquid or gas, the nozzle member may beprovided in an inner side of the top wall with a groove connected to thenozzle hole and a groove connected to the air hole. Each groove iscovered with the hydrophilic filter or hydrophobic filter.

In a preferred embodiment, the liquid drug container of the presentinvention is provided on its nozzle cap with a sealing portion forsealing the tip of the nozzle member.

In another preferred embodiment of the liquid drug container accordingto the present invention, the hydrophilic filter and the hydrophobicfilter are arranged separately either on upper or lower side of the topwall so as not to interfere with one another.

In another preferred embodiment of the present invention, the liquiddrug container comprises a flexible body having a mouth at one end andbeing easily deformable under the pressure; and a nozzle memberliquid-tightly mounted on the mouth of said body; characterized in thatsaid nozzle member is provided with a nozzle hole and an air hole whichcommunicate an interior of the container body with the atmosphere, ahydrophilic filer covering said nozzle hole, a hydrophobic filtercovering said air hole, and a flow control member for controlling inflowof the air to the interior of the container body through said air hole.

In another preferred embodiment, the nozzle member is provided with anozzle-communicating hole and a flow control member for controlling theair that flows into the interior of the container body through saidnozzle-communicating hole.

In still another preferred embodiment, the nozzle member is providedwith a flow control member that controls air flowing into the containerbody through the nozzle-communicating hole.

In another embodiment, the nozzle member is provided with afilter-mounting member having a nozzle-communicating hole and anair-communicating hole, which respectively communicated with the nozzlehole and air hole, the filter-mounting member is provided with a flowcontrol member that controls air flowing into the container body fromthe exterior thereof through the nozzle-communicating hole andair-communicating hole. The flow control member may be a check valve ora diaphragm.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention, and wherein:

FIGS. 1 and 1A are longitudinal sections of a liquid drug container ofthe present invention;

FIGS. 2 and 2A are exploded bottom plan views of a bottle cap with afilter being removed;

FIG. 3 is a partially cutaway perspective illustration of a liquid drugcontainer of the present invention;

FIG. 4 is an exploded perspective view of a liquid drug containerillustrating another embodiment of the present invention;

FIG. 5 is a sectional view of the liquid drug container shown in FIG. 4;

FIG. 6 illustrates a filter-mounting member used in the liquid drugcontainer of FIG. 4, in which Figure (A) is a plan view, Figure (B) is asection view, and Figure (C) is a bottom plan view;

FIG. 7 illustrates a filter-mounting member equipped with a filter,figure (A) is a plan view, and figure (B) is a bottom plan view;

FIG. 8 is an exploded perspective view of a liquid drug containeraccording to one embodiment of the present invention;

FIG. 9 is a sectional view of the liquid drug container.

FIG. 10 is a filter-mounting member provided with no filter, including aplan view shown in the figure (A), a section view shown in the figure(B), and a bottom plan view shown in figure (C);

FIG. 11 is a filter-mounting member provided with a filter, including aplan view shown in the figure (A), and a bottom plan view shown in thefigure (B);

FIG. 12 illustrates a check valve 41, illustrated as a section view of aclosed condition in Figure (A) and as a section view of an opencondition in figure (B),

FIG. 13 is a section view of the filter-mounting member provided with acheck valve used for a liquid drug container according to anotherembodiment of the present invention; and

FIG. 14 is a section view of a liquid drug container of the prior art,illustrating details of a mouth thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention will be explained below in detailto clarify the present invention more concretely, making reference toaccompanying drawings. In the drawings, the same reference numeralsdenote the same or equivalent throughout the figures.

FIG. 1 is longitudinal section of a liquid drug container of the presentinvention; FIG. 2 is an exploded bottom plan view of a bottle cap shownin FIG. 1 (illustrated is a condition where a filter is removed); andFIG. 3 is a partially cutaway perspective illustration of a liquid drugcontainer of the present invention.

As shown in FIG. 1, a liquid drug container of the present inventioncomprises a body 1, a bottle cap or a nozzle member 2 liquid-tightlymounted on the container body 1, and a nozzle cap 6 mounted on thenozzle member 2. An nozzle hole 231 of the nozzle member 2 is coveredwith a hydrophilic filter 3. The nozzle member 2 is provided in a topwall 22 thereof with an air hole 24 that is covered with a hydrophobicfilter 4.

The container body 1 is usually formed in the configuration of abottom-closed cylinder and is provided at a top thereof with a mouthportion 12 having a diameter smaller than that of a barrel portion 11. Amaterial used for the container body is a flexible polymeric materialthat is deformable under the pressure and easily restorable to itsoriginal configuration at the time of releasing from pressing. Such aflexible polymeric material includes various polymeric material havingelasticity, such as polypropylene, polyethylene, polyethyleneterephthalate, polyethylene terenaphthalate, polyester, plasticizedpolyvinyl chloride, thermoplastic elastomer and polycarbonate.

The nozzle member 2 is a cap-shaped member and is provided with a skirtportion 21 extending from the peripheral portion of the top wall 22towards a proximal end thereof. As required, a gasket 7 may be arrangedBetween skirt portion 21 and mouth portion 12 of the container body 1.The nozzle 23 is made into a cylindrical form or a truncated coneconfiguration projecting from the top wall 22 of the nozzle member 2towards the distal end thereof. The nozzle 23 is provided with a nozzlehole 231 longitudinally passing therethrough and serving as a flow pathfor liquid. A proximal end of the nozzle hole 231 is covered with ahydrophilic filter 3 arranged on the inner wall of the top wall 22.

In the above-preferred embodiment, the nozzle member 2 is provided onits top wall 22 with a cylindrical wall 25 coaxially with the nozzle 23.The air hole 24 is so formed in the top wall 22 as to pass through aportion of the top wall 22 between nozzle 23 and cylindrical wall 25.The air hole 24 is covered with a hydrophobic filter 4 arranged on theinner side of top wall 22. If the air hole 24 is provided in a positionseparated from the nozzle hole 231, it is not necessarily required toprovide the cylindrical wall 25 on the top wall.

According to the present invention, proper air flow of the air hole 24is ensured by providing the air hole 24 covered with the hydrophobicfilter 4 in a different position separated from the nozzle hole 231covered with the hydrophilic filter 3.

Filters 3 and 4 are generally mounted on the inner side of the nozzlemember by welding. The welding includes ultrasonic welding,high-frequency welding and thermal welding. A preferred method in thepresent invention is thermal welding.

It is preferred that the hydrophilic filter and hydrophobic filter havea bore size of 0.45 μm or below, more preferably, 0.22 μm or below toprevent Candida albicans, Pseudomonas genera and Burkholderiacepacia,which are generally known as pollutive bacteria, from invading theinterior of the container. A trapping mechanism of the filter isclassified broadly into two categories, i.e., a “depth type” that trapsbacteria within the filter, and a “screen type” that traps bacteria onsurfaces of the filter. Any type of the filter can be used for thepresent invention.

Air flow and liquid flow can be improved by providing the inner side ofthe top wall 22 of the nozzle member 2 with grooves 51 that communicatewith the nozzle hole 231 and grooves 52 that communicate with the airhole, and welding filters 3 and 4 so as to cover the grooves 51 and 52respectively, as shown in FIG. 2. In this case, there is no fear thatthe filter with a large filtration area peels off or becomes damaged atthe time of pressing even if the filter is welded to the nozzle member 2at an outer edge thereof.

The nozzle cap 6 is made in the form of approximate cylinder with amouth. The nozzle cap 6 is provided with a sealing portion 61 thatprotrudes inwardly from the top wall of the cap 6 and comes into closecontact with the tip of the nozzle 23 to air-tightly seal the nozzlehole 231. The sealing portion 61 is generally formed into a cylindricalform.

In this embodiment, the nozzle cap 6 is designed so as to bescrew-mounted or fitted on the cylindrical wall 25. If there is nocylindrical wall 25, the nozzle cap 6 is so designed as to bescrew-mounted or fitted on the skirt portion 21 of the nozzle member 2.The nozzle cap 6 may be a member adapted to be fitted on the nozzle 23,e.g., a rubber cap configured only by a sealing portion 61.

Since the nozzle hole of the nozzle member is covered by the hydrophilicfilter and since the nozzle member is provided with the air hole coveredwith the hydrophobic filter separate from the nozzle hole, the aboveliquid drug container of the present invention makes it possible toprevent bacteria and microorganism from invading the interior of thecontainer even if the nozzle of the liquid drug container is broughtinto contact with the skin at the time of use.

The liquid drug container of the present invention has remarkableeffects when used for liquid drugs requiring higher abacterial thancosmetics, in particular, when used as an eyedropper for holding anophthalmic solution limited in addition of a preservative.

Referring now to FIG. 4 to FIG. 7, there is shown another embodiment ofthe liquid drug container according to the present invention.

The Liquid drug container of this embodiment comprises a flexiblecontainer body 1 easily deformable under the pressure, and a nozzlemember 2 liquid-tightly attached to the container body and provided witha nozzle and an air hole that communicate an interior of the containerbody to the exterior thereof. The liquid drug container is provided witha hydrophilic filter 3 for covering the nozzle of the nozzle member 2, ahydrophobic filter 4 for covering the air hole, and a filter-mountingmember 8. The filter-mounting member 8 holds the hydrophilic filter 3and the hydrophobic filter 4 within the nozzle member 2 separately oneither an upper and lower side thereof so that they do not causeinterference with each other.

As best shown in FIG. 4, the container body 1 is a bottom-closedcylindrical container of a flexible polymeric material. The containerbody 1 has a mouth 12 with a diameter smaller than that of a barrel 11at a top thereof, and is provided on an external wall of a neck portionthereof with a male thread 13 for engagement with the nozzle member 2mentioned below.

The nozzle member 2 is a cap-shaped member comprised of a discoid topwall 22 covering mouth of container body 1 and a skirt portion 21hanging down from the outer edge part of the top wall 22. The skirtportion 21 is provided in an inner wall thereof with a female screw 211.This female screw 211 is adapted to be engaged with the male screw 13 ofthe mouth 12. Thus, the container body 1 can be sealed liquid-tightly byscrew-mounting the nozzle member 2 on the mouth portion.

The top wall 22 is provided at a central part thereof with a nozzle 23that protrudes on the opposite side of the skirt portion. The nozzle 23is made into a cylindrical form or a truncated cone form and is providedwith a nozzle hole 231 longitudinally passing through the nozzle andserving as a liquid flow path. The nozzle member 2 is further providedwith a cylindrical wall 25 extending coaxially with the nozzle 23 fromthe top wall 22 of the nozzle member and surrounding the nozzle 23. Thecylindrical wall 25 is provided in an external wall thereof with malescrew 26.

The top wall 22 of the nozzle member 2 is provided with an air hole 24passing through the top wall 22 at a position between the nozzle 23 andcylindrical wall 25. The air hole 24 is not always limited to onelocation, and may be formed in several locations.

The filter-mounting member 8 is a generally disc-shaped member andincludes a disc-shaped body 81 and a skirt portion 82 formed in the formof a ring on the opposite side of the mounting side, as shown in detailin FIG. 6. An external diameter of the disc-shaped body 81 is set to asize that fits into the bore of the nozzle member 2, and an externaldiameter of skirt portion 82 is set to a size that fits into the openingof the mouth 12 of the container body 1.

Thus, the filter-mounting member 8 can be fixed between the mouth 12 andthe backside of nozzle member 2 as shown in FIG. 5. This may be done byinserting the filter-mounting member 8 into the bore of the nozzlemember 2, and then engaging the nozzle member 2 with the mouth 12 of thecontainer body 1.

The filter-mounting member 8 is provided with a small cylindricalprojection 83 projecting from an upper central part of the mounting side81. Also, the filter-mounting member 8 is provided with anozzle-communicating hole 84 passing through a central part of thecylindrical projection 83 and extending from the top of the cylindricalprojection 83 to the opposite end of the mounting side 81.

The opposite side of the mounting side 81 is provided with a set ofgrooves 85 around the nozzle-communicating hole 84. The set of grooves85 include radial grooves 85 a communicated with thenozzle-communicating hole 84 and annular grooves 85 b communicated withthe radial grooves 85 a.

Also, an air-communicating hole 86 is provided at a position radiallyand outwardly spaced from the center of the mounting side 81 and on theinner side of the skirt portion 82. Provided on the upper side ofmounting side 81 and around the air-communicating hole 86 is a set ofgroove 87. The set of groove 71 includes radial grooves 87 acommunicated with the air-communicating hole 86 and annular groove 87 bcommunicated with the radial grooves 87 a.

In the embodiment with the above structure, as shown in FIG. 5, thefilter-mounting member 8 is fixed on the upper part of the mouth portion12 by screw-mounting the nozzle member 2 on the mouth portion 12 of thecontainer body 1. Under such a condition, the nozzle hole 132 of thenozzle 23 is communicated with the interior of the container body 1through the nozzle-communicating hole 84, while air hole 24 iscommunicated with the interior of the container body 1 through theair-communicating hole 36.

As shown in FIGS. 5 and 7, the hydrophilic filter 3 is attached to thebottom face of the filter-mounting member 8, while the hydrophobicfilter 4 is attached to the top face of the filter-mounting member 8.

The hydrophilic filter 3 and hydrophobic filter 4 are formed in a flatmembrane and are members that can be mounted by welding. The usablewelding process includes ultrasonic welding, high-frequency welding andthermal welding. In the present invention, it is preferred to usethermal welding.

As shown in FIG. 7, it is possible to cover the nozzle-communicatinghole 84 and groove 85 by welding the hydrophilic filter 3 onto thegroove 85 and surrounding area thereof on the bottom side of thefilter-mounting member 8. In the drawings, reference numeral 88 denotesa positioning rib for the hydrophobic filter 4.

In the present embodiment, the hydrophilic filter 3 and hydrophobicfilter 4 do not cause interference with each other since they areseparately arranged on the top and bottom sides of the filter-mountingmember 8. Further, it is possible to use large sized filters 3 and 4unless the diameter of each filter 3, 4 exceeds the diameter offilter-mounting member 8.

In this way the diameter of hydrophilic filter 3 which directly have aninfluence on easiness of discharge easiness of liquid drug was enlargedto the inner diameter of skirt portion 82 of filter-mounting member 8.Thus, the present embodiment make it possible to realize considerablygood discharge characteristics of the liquid drug even if the hole ofthe hydrophilic filter 3 is reduced in diameter.

As the filters 3 and 4, there have been used such filters each having abore size of 0.45 μm or below, preferably, 0.22 μm or below to preventcontamination source bacteria from invading the interior of thecontainer.

The trapping mechanism of the filter is classified broadly into twocategories, i.e., a “depth type” that traps bacteria within the filter,and a “screen type” that traps bacteria on surfaces of the filter. Anytype of the filter can be used for the present invention.

As illustrated in FIGS. 4 and 5, the nozzle cap 6 is a generallycylindrical member opened at a bottom thereof and closed at the top. Thenozzle cap 6 is provided on the internal surface side of its top wallwith a sealing portion 61, which is brought into close contact with atip of the nozzle 23 to hermetically seal the nozzle hole 231 of thenozzle 23. The sealing portion 61 is generally formed into a cylindricalconfiguration.

In this embodiment, the nozzle cap 6 is screw-mounted or engaged withthe cylindrical wall 25 of the nozzle member 2. If the nozzle member 2has no cylindrical wall 25, the nozzle cap 6 is so designed as to bescrew-mounted or engaged with the peripheral portion of the skirtportion 21 of the nozzle member 2. The nozzle cap 6 may be a member tobe fitted on the nozzle 23, e.g., a rubber cap configured only by asealing portion 61.

In the above embodiment, the hydrophilic filter 3 is mounted on thebottom side of the filter-mounting member 8, while the hydrophobicfilter 4 is mounted on the top of the filter-mounting member 8. Contraryto this embodiment, the hydrophilic filter 3 may be mounted on the topof the filter-mounting member 8, and the hydrophobic filter 4 may bemounted on the bottom side of the filter-mounting member 8. In thatcase, the hydrophilic filter 3 may be welded without trouble, providedthat cylindrical projection 83 is removed to make the top offilter-mounting member 8 flat.

In the above embodiment, the filter-mounting member 8 was used to mountthe hydrophilic filter 3 and hydrophobic filter 4 on the nozzle member.However, the hydrophilic filter 3 and hydrophobic filter 4 may beattached directly to the nozzle member 2 without use of thefilter-mounting member. In that case, the hydrophilic filter 3 is weldedto the inner side of the top wall 22 of the nozzle member 2 that hasbeen provided with a groove communicating with the nozzle hole 231,while the hydrophobic filter 4 is welded to the outer side of the topwall that has been provided with a groove communicating with the airhole 24. The hydrophobic filter 4 can be covered with a large-sizednozzle cap 6 (see FIGS. 1A and 2A).

The liquid drug container of the present invention has remarkableeffects when used for liquid drugs requiring higher abacterial thancosmetics, in particular, when used as an eyedropper for holding anophthalmic solution limited in addition of a preservative.

Since the liquid drug container of the present invention is providedwith the air hole in addition to the nozzle hole, and since the nozzlehole and the air hole are respectively covered with the hydrophilicfilter and hydrophobic filter each having a small bore size, it ispossible to prevent microorganism known as contamination cause bacteriafrom invading the interior of the container without decrease in easinessof handling. In addition, the hydrophilic filter and hydrophobic filterare separately arranged on either upper or under side of the top wall orof the filter-mounting member, and do not cause interference with eachother, thus making it possible to widen effective areas of respectivefilters. Thus, this makes it easy to discharge the liquid drug andallows the deformed container to return to the original configurationwith ease.

Use of the filter-mounting member makes it possible to arrange thehydrophilic filter and hydrophobic filter can be arranged at differentlevels without causing complicated structure of the nozzle member. Inthat case, the hydrophilic filter and hydrophobic filter are separatelyattached to inner and outer sides of the filter-mounting member.

The filter-mounting member can be fitted in the interior of the nozzlemember and sandwiched between the internal surface of the nozzle memberand mouth portion of the container body. Thus, it is easy to incorporatethe hydrophilic filter and the hydrophobic filter, which should bearranged on upper and lower levels, into the container.

Further, the liquid drug container can be made into compact since theabove two kinds of filters are in the form of a flat membrane, of whicha mounting space is very small.

The provision of the grooves makes it possible to improve the liquiddrug flow at the time of discharge as well as to improve the airflow atthe time of inflow of the air, thus making it possible to improveuser-friendliness of the container.

A liquid drug container shown in FIGS. 8–12 comprises a container body1, a cap-shaped nozzle member 2 and a nozzle cap 6. The nozzle member 2is provided with a nozzle hole 231 and air hole 24, which communicatethe interior of the container body 1 with the exterior thereof.

The nozzle member 2 is further provided with a hydrophilic filter 3covering the nozzle hole 231, and a hydrophobic filter 4 covering airhole 24. These members have approximately the same constructions asthose of the corresponding members of the liquid drug container shown inFIG. 1.

The liquid drug container 1 in this embodiment further comprises afilter-mounting member 8 in addition to the aforesaid constituentmembers. The filter-mounting member 8 is an approximately disc-shapedmember and is comprised of a disc-shaped body 81 and an annular skirtportion 82 formed on the bottom of the disc-shaped body 81, asillustrated in detail in FIG. 10. An external diameter of thedisc-shaped body 81 is set to proper size for fitting into the skirtportion 21 of nozzle member 2. An external diameter of the skirt portion82 is set to proper size for fitting into the mouth 12 of the containerbody 1.

The disc-shaped body 81 is provided at a central portion thereof with asmall cylindrical projection 83 and a nozzle-communicating hole 84passing through the center of cylindrical projection 83 and extendingfrom the upper end of the cylindrical projection 83 to the bottom faceof the disc-shaped body 81. The nozzle-communicating hole 84 iscommunicated with the nozzle hole 231 of the nozzle 23. The disc-shapedbody 81 is provided in its bottom face with grooves 85 surrounding thenozzle-communicating hole 84. The grooves 85 include radial grooves 85 acommunicated with the nozzle-communicating hole 84, and annular groove85 b communicated with these radial grooves 85 a.

The disc-shaped body 81 is further provided with air-communicating hole86 at a position radially spaced from the center thereof but inside ofthe skirt portion 82. The air-communicating hole 86 passes through thedisc-shaped body 81 from its top to the bottom. The disc-shaped body 81is provided with grooves 87 around the air-communicating hole 86 on thetopside of the disc-shaped body 81. The grooves 87 include radialgrooves 87 a communicated with the air-communicating hole 86, andannular groove 87 b communicated with these radial grooves 87 a. Thus,the air-communicating hole 86 is communicated with the air hole 24through the grooves 87.

Furthermore, the disc-shaped body 81 is provided with a flow controlmember 41 for controlling air flowing into the container body 1 throughthe air hole 24. The flow control member 41 may have any construction,provided that it has a function to limit the flow rate of the air. Inthe present invention, a preferred flow control member includes checkvalves and diaphragms, but any other flow control member may be used asthe flow control member 41. The diaphragms include choke valves andorifices.

In the above embodiment, a check valve 41 is provided in theair-communicating hole 86 which is a flow path from the air hole 24 tothe container body 1. The check valve 41 may be formed as an integralpart of the filter-mounting member 8 or as a separate member to befitted into and fixed to the filter-mounting member 8. If the checkvalve 41 is formed as an integral part of the filter-mounting member 8,a valve body of the check valve 41 is required to have elasticity. Thereis no limit to a material for the filter-mounting member 8, providedthat it is a soft material with elasticity and allows the filter to bewelded thereto. A specific material for the filter-mounting memberincludes for example, thermoplastic elastomer and polyolefin resins(low-density polyethylene, random polypropylene). On the other hand,when the check valve 41 is provided as a separate member, a material forcheck valve 41 includes, silicone rubber and vulcanized rubber such asisobutylene-isoprene rubber in addition to the aforesaid thermoplasticelastomer and polyolefin resins. In this case, as a raw material offilter-mounting member 8, there may be used any polymeric material whichhas been time-proven as a medical device material.

As shown in FIG. 12, the check valve 41 is directed so that it preventsoutflow of the liquid drug (d) to the exterior of the container body(cf. FIG. 12A) but permits inflow of air (a) to the interior of thecontainer body (cf. FIG. 12B).

Thus, when discharging the liquid drug from the nozzle hole 231 underthe pressure the container body 1 with fingers, the liquid drug (d) isshut off by the check valve 41 and prevented from entering into theair-communicating hole 86, as shown in FIG. 12 (A). The same applies tothe container body 1 in the normal state. When losing the pressure offingers from the pressed container body 1, the container body 1 beginsto swell up to the original configuration and the ambient air (a) beginsto flow in the container body 1 through the air hole 24 and theair-communicating hole 86. At that time, the check valve 41 is openedslightly by a differential pressure between the atmosphere and anegative pressure in the container body 1 as shown in FIG. 12(B). Thus,the ambient air (a) flows into the container body through a narrowopening of the check valve 41.

As shown in FIG. 9, the filter-mounting member 8 is fixed on the top ofmouth 12 by screw-mounting the nozzle member 2 on the mouth ID of thecontainer body 1. Under such a condition, the nozzle hole 231 of thenozzle 23 is communicated with the interior of container body 1 throughthe nozzle-communicating hole 84, while the air hole 24 is communicatedwith the interior of container body 1 through air-communicating hole 86.

As shown in FIGS. 9 and 11, the hydrophilic filter 3 is attached to thebottom of the filter-mounting member 8, while the hydrophobic filter 4is attached to the top of filter-mounting member 8.

In use, the nozzle cap 6 is removed firstly from the liquid drugcontainer. Then, the container body 1 is pressed by fingers to dischargea liquid drug contained therein, the liquid drug is pushed out anddropped from the nozzle 23 through the hydrophilic filter 3. At thattime, the check valve 41 is closed as shown in a figure of FIG. 12 (A)so that the liquid drug (d) does not enter into the air-communicatinghole 86 and is kept in the condition out of contact with the hydrophobicfilter 4. Thus, even if the liquid drug is incompatible with thematerial for hydrophobic filter 4, the hydrophobic filter 4 can beprevented from being deteriorated (for example, being changed tohydrophilic). Further, it is possible to prevent crystal deposition ofthe drug on the underside of the hydrophobic filter 4 (in the groove87). In addition, it is possible to prevent growth of bacteria that takethe liquid drug in the groove 87 as nutrients and display hyphaldevelopment on the top of the hydrophobic filter, for example,Aureobasdium Pullulans or Aspergillus Oryzac. This contributes tosterilization of the liquid drug.

After dropping a certain amount of the liquid drug, the container body 1is loosed from the pressure. Thus, the container body 1 begins to expandso as to return to the original configuration due to its flexibility. Atthat time, the internal pressure of the container body 1 becomesnegative. Because of a pressure difference between the negative pressureand the atmosphere pressure, the liquid drug which remains in the insideof nozzle hole 231 collected after stopping of discharge is returned inthe container body 1 through the hydrophilic filter 3. On the otherhand, the check valve 41 opens slightly as shown in figure of FIG. 12(B), so that the ambient air (a) flows into the in container body 1little by little even after the remaining liquid drug was returned inthe container body 1. Thus, the container body 1 is restored to itsoriginal configuration slowly for a length of time, which in turn makesit possible to take enough time to allow the liquid drug remained on thehydrophilic filter 3 to be returned in the container body 1.

In this way, the negative pressure in the container body 1 ensures anadequate time required for the liquid drug to pass through thehydrophilic filter 3, thus making it possible to avoid retention of theremaining liquid drug in nozzle hole 231. Accordingly, it is possible tominimize a fear that the bacteria-contaminated liquid drug enters in theinterior of the container body 1.

FIG. 13 illustrates another embodiment of the present invention, using athin valve body as a check valve. Since the valve body is thin, thecheck valve 42 becomes sensitized to and is apt to be easily opened bythe negative pressure in container body 1. However, if the valve body isthinned too much, the valve body opens too much, which in turn shortensthe time for the liquid drug in the nozzle hole 231 to pass through thehydrophilic filter 3. Thus, the thickness the valve body is sodetermined that the flow of the liquid drug takes a suitable timeperiod.

In each of the above embodiments, the check valve has been used as theflow control member. It is possible to substitute a diaphragm for thecheck valve. The diaphragm may be an orifice or a choke. The choke is adiaphragm with a length longer than a size of cross section of anopening, while orifice is a diaphragm having a length shorter than asize of cross section of an opening. In either diaphragm, it issufficient to use the diaphragm if it ensures an enough time required toallow the liquid drug to pass through the hydrophilic filter 3 when theliquid drug in the nozzle hole 231 returns to the container body 1. Thisembodiment can also prevent bacteria from adhering to the liquid drug asis the case with the aforesaid embodiment, thus making it possible toobtain the same effect as that of the liquid drug container shown inFIG. 4.

In each embodiment, the check valve or the diaphragm has been arrangedin the air-communicating hole 86 formed in the filter-mounting member 8.In an embodiment having no filter-mounting member 8, the check valve orthe diaphragm may be arranged in an airflow path between the air hole 24and the container body 1, e.g., in the air hole 24 or in the top wall 22of the nozzle member 2.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

1. A liquid drug container comprising a container body (1) having a mouth (12) and being deformable under the pressure, a cap-shaped nozzle member (2) liquid-tightly mounted on the mouth (12) of the container body (1), and a nozzle cap (6) mounted on the nozzle member (2), wherein said nozzle member (2) comprises a top wall (22) covering the mouth (12) of said container body (1), a skirt portion (21) extending from a peripheral portion of the top wall (22) toward a proximal end of the nozzle member (2), and a nozzle (23) extending from a central portion of said top wall (22) toward a distal end of the nozzle member (2), wherein said nozzle member (2) has a nozzle hole (231) passing through the top wall (22) to discharge a liquid drug contained in said container body (1), and an air hole (24) passing through the top wall (22) at a position separated from said nozzle hole (231) to allow an interior of said container body (1) to communicate with the outside thereof, wherein said nozzle member (2) is provided with a disk-shaped filter-mounting member (8) in said skirt portion (21), wherein said disk-shaped filter-mounting member (8) is provided with sets of grooves (85, 87) respectively communicated with said nozzle hole (231) and air hole (24), wherein said filter-mounting member (8) is provided with a hydrophilic filter (3) and a hydrophobic filter (4), and wherein said hydrophilic filter (3) is arranged on and welded to one side of said filter-mounting member to cover one set of grooves (85) communicated with said nozzle hole (231), while the hydrophobic filter (4) is arranged on and welded to the opposite side of said filter-mounting member to cover said air hole (24) and the other set of grooves (87) communicated with said air hole (24) as well as to avoid interference from said hydrophilic filter (3).
 2. The liquid drug container according to claim 1, wherein each set of grooves (85, 87) include radial grooves (85 a, 87 a) communicated with the nozzle-communicating hole (84) or air-communicating hole (86) and annular grooves (85 b, 87 b) communicated with the radial grooves (85 a, 87 a).
 3. The liquid drug container according to claim 2, wherein said hydrophilic filter (3) and hydrophobic filter (4) are in the form of a flat membrane.
 4. The liquid drug container according to claim 1, wherein said hydrophilic filter (3) and hydrophobic filter (4) have a bore size of not more than 0.45 μm.
 5. The liquid drug container according to claim 4, wherein said hydrophilic filter and hydrophobic filter have a bore size of not more than 0.22 μm.
 6. The liquid drug container according to claim 1, wherein said disc-shaped filter-mounting member (8) is arranged in the skirt portion (21) and in close contact with an inner side of the top wall (22) of said nozzle member (2), wherein said disk-shaped filter-mounting member (8) is provided at a central portion thereof with a nozzle-communicating hole (84) passing therethrough and being communicated with said nozzle hole (231), and at a position spaced from said nozzle-communicating hole (84) with an air-communicating hole (86) passing therethrough and being communicated said air hole (24) through said grooves (87).
 7. The liquid drug container according to claim 1, wherein is provided with a flow control member (41) that controls air flowing into the container body from the exterior of the container body (1) through the air hole (24), said flow control member (41) being arranged in the air-communicating hole (86).
 8. The liquid drug container according to claim 7, wherein said air-communicating hole is provided with a flow control member that controls the air flowing into the container body from the exterior of the container body.
 9. The liquid drug container according to claim 8, wherein said flow control member is a check valve or a diaphragm.
 10. A liquid drug container comprising a container body having a mouth and being deformable under the pressure, a cap-shaped nozzle member liquid-tightly mounted on the mouth of the container body, and a nozzle cap mounted on the nozzle member, wherein said nozzle member comprises a top wall covering the mouth of said container body, a skirt portion extending from a peripheral portion of the top wall toward a proximal end of the nozzle member, and a nozzle extending from a central portion of said top wall toward a distal end of the nozzle member, wherein said nozzle member has a nozzle hole passing through the top wall to discharge a liquid drug from said container body, and an air hole passing through the top wall at a position separated from said nozzle hole to allow an interior of said container body to communicate with the outside thereof, wherein the top wall of said nozzle member is provided on one side thereof with a set of grooves communicated with said nozzle hole, and on the opposite side with a set of grooves communicated with said air hole, wherein said top wall is provided with a hydrophilic filter and a hydrophobic filter, and wherein said hydrophilic filter is arranged on and welded to one side of said top wall to cover said nozzle hole and one set of grooves communicated with said nozzle hole, while the hydrophobic filter is arranged on and welded to the opposite side of said top wall to cover said air hole and the other set of grooves communicated with said air hole as well as to avoid interference from said hydrophilic filter (3).
 11. The liquid drug container according to claim 10, wherein each set of grooves include radial grooves (51 a, 52 a) communicated with the nozzle hole (231) or air hole (24), and annular grooves (51 b, 52 b) communicated with the radial grooves (51 a, 52 a).
 12. The liquid drug container according to claim 10, wherein said hydrophilic filter and a hydrophobic filter are in the form of a flat membrane.
 13. The liquid drug container according to claim 10, wherein said hydrophilic filter and hydrophobic filter have a bore size of not more than 0.45 μm.
 14. The liquid drug container according to claim 10, wherein the nozzle member is provided with a flow control member that controls air flowing into the container body from the outside through the air hole, said flow control member being arranged in the air hole.
 15. The liquid drug container according to claim 14, wherein said flow control member is a check valve or a diaphragm. 